8x4=32
32=(yx7)-(yx3)
(yx7)=7y
(yx3)=3y
32=7y-3y
7y and 3y are like terms so you subtract them
=4y
32=4y
then divided 4y by 4 (to get y on its own) this cancels out if you ÷ 4y on one side of the equation you have to divide on the other side to make it balanced 32÷4=8
y=8